The imposing geological feature is called Umm al-Biyara, a name that derives from the Arabic word for 'cistern'. The name is probably due to the large number of water cisterns found there, many of which date back to the Edomite period. A difficult path climbs 1000m above sea level to the top where the plateau served as an easily defended fortress for thousands of years.At the summit there is a 7- 8"century BC, consisting of small houses built using rough stones without mortar.A seal of Qos-Gaber, an Edomite king of the 7th century BC, was found there